The present invention relates to a method for the automatic grading and cutting of articles, such as garment pieces, of different sizes corresponding to a predetermined scale of sizes and having size proportions similar to those of a predetermined basic model pattern.
Grading is the operation which consists in obtaining different sizes, either larger or smaller, in relation to a pre-established scale, of sizes, starting from a basic model pattern produced for a basic size, in order to constitute a family of articles of two or three sizes, which are all different but remain similar in design to the basic pattern.
Grading operations are necessary in all those fields where lines of articles of different sizes which have to correspond to a basic pattern, are produced, but grading becomes more difficult in the case of articles required to adapt to the human body, since the volume of such articles has to evolve according to more or less complex scales of sizes, taking into account the actual evolution of the morphology of the human body. This is the case with the production of garments or with the production of related fields such as lingerie, haberdashery, or the hat, shoes, or even leather good industries.
Garments are generally produced by the assembling together of different pieces, each one of which is cut from a basic pattern or model, which is in the form of a plane developed surface with a particular outline, with in certain cases, additional markings inside said outline.
For every piece of garment, the grading operation consists in defining, from the basic pattern corresponding to a basic size, other patterns similar to the basic one, but adapted for the different sizes, in order to allow subsequent cutting of the pieces for the different sizes, from the material which will constitute the garment, namely fabrics, leather or any other selected synthetic or natural material.
It is already known to mark out on the basic pattern, characteristic points, also called outline points, permitting to reconstitute the whole of the image of the pattern with, if necessary, other markings inside thereof. Grading then essentially consists, for each different size, in determining the characteristic points corresponding to the characteristic points of the basic pattern, wherefrom the image of the basic pattern of the considered size, can be automatically drawn, this in itself further permitting an automatic cutting. The determination from the basic pattern of the various characteristic points for the various sizes, still remains a manual operation, which is long and difficult and necessitates a specially trained staff. It may also happen that after a manual grading of this kind, all the patterns taken from the basic pattern, have to be altered. In the case of semi-automatic methods of grading and cutting, in which the garment pieces are directly cut from the images taken from the basic pattern, without patterns being really made for other sizes but the basic size, the necessity of having to make a test series causes not only a waste of time, but also a waste of material.